Ice hockey skates today generally comprise a sharpened metal blade or runner fastened to a holder, which is in turn fastened to a skate boot. Goaltender skates are similar, but further have a cowling to protect the lower portion of the skate boot, which might be connected to or formed integrally with the holder. Speed skates also generally comprise a sharpened metal blade held by a holder, which is then fastened to a skate boot, although the overall look and configuration of the skate is different than an ice hockey skate. In all cases, when the blade of a skate becomes dull, the surface of the blade that contacts the ice surface is re-sharpened, either to provide a hollow between a set of opposed inner and outer edges, or, in the case of a goalie skate, to provide offset or flatter edges across the thicker blade.
Current methods of skate sharpening generally require that the skate be removed from a wearer's foot. If a skater notices that a blade has become dull while he or she is on the ice, it is generally necessary to remove the skate, take it to a skate sharpening machine, sharpen the blade, and replace the skate on the skater's foot before returning to the ice. During a hockey or ringette game or a skating competition, this may be an unacceptable amount of time to be away from the ice. If there is no skate sharpener readily available, the time away from the ice is necessarily increased. The alternative is to skate on dull blades, which adversely affects the skater's speed, mobility and ability to perform necessary manoeuvres.
It is therefore preferable to be able to replace a dull blade or to simply replace an unsatisfactory blade without having to remove the skate boot from a skater's foot. U.S. Pat. No. 1,591,778 discloses a reversible blade made of a single piece of metal shaped into a generally I-shaped cross-section. The blade is meant to be reversed when one edge gets dull, and then both edges must be sharpened once both edges have become dull. There exist several other examples of removable blade systems, such as U.S. Pat. No. 6,419,241 to Chenevert, U.S. Pat. No. 6,485,033 to Nicoletti et al. and Applicant's co-pending PCT App. No. PCT/CA2012/000968, which disclose a skate blade that may be removed from a skate by removal of one or more threaded fasteners, and replaced with a new blade that is then secured with those fasteners. However, while having a reversible blade will help alleviate the urgency of finding a way to provide a freshly sharpened blade when a minimal amount of time is available, or when a skilled sharpener is not available, it is possible that a skater will suddenly find that he has used and dulled both edges of a blade.
As a further consideration, each time the blade is sharpened using standard sharpening machines and techniques, metal is physically removed from the ice-contacting or runner portion of the blade; each time metal is removed during a sharpening, the balance and feel of the skate may change. Over time the skate will eventually run out of metal blade available for sharpening, necessitating complete replacement of the blade. Because of the configuration of many skates, especially ice hockey skates, this often results in the need to either replace the entire holder or even the entire skate. Further, many skaters are particular about how their blades are sharpened, in terms of having the desired profile (radius and rocker) and hollow radius, as changes to those parameters can adversely affect the feel of the skates, and therefore the performance of the skater in a game or competition. A skater therefore must find a person who can consistently sharpen the blades to the skater's preferences, and would obviously then prefer to take the skates to that person every time. This can result in difficulty if, for example, the skater has travelled to another rink or another city for a game or competition. It is therefore preferable to provide a skate blade that does not ever need sharpening, so that when it is replaced, it reliably and consistently has the exact properties that the skater is expecting.
Further, different ice surfaces will have different properties; temperature, humidity and water quality vary from rink to rink and will produce ice surfaces that may be harder or softer than the skater is used to. As the skater may not realize how the ice feels until he has been on it for a while, such as after a warm-up, it may not be convenient or even possible to have a skate blade sharpened especially for that surface. The same considerations might even arise during a game or competition, as the temperature and humidity of the air around the rink can change substantially over time, for example if there are many spectators surrounding the rink. Again, it is likely inconvenient or impossible to have the skates sharpened for such changing conditions, as well as of course removing the metal from the blade even faster.
In such situations, it can be preferable to have a number of blades, each with varying characteristics such as with blade thicknesses, profiles (radius and rocker) and hollow radii, so that a dull or unsuitable blade can quickly be replaced with another having the properties required for the current ice surface and skating conditions. However, the cost of buying several sets of reversible blades, as well as the cost of having each sharpened twice as it becomes dull, can become prohibitive.
U.S. Pat. No. 2,242,870 discloses a reversible, double-edged blade composed of a single shaped piece of metal having a generally I-shaped cross-section. This blade is specified to be disposable, as no sharpening of the blade is contemplated. However, the presence of a substantially thinned area along the central length of the blade may tend to destabilize the blade under the lateral torque forces typically created during the skating stride and when performing other manoeuvres. A blade made completely of metal, while strong and tough, also tends to be heavy and expensive to manufacture.
Providing solid metal blades that have to be machined into various configurations, is therefore unlikely to help reduce the costs associated with carrying several sets of blades.
Because of the limitations of an all-metal blade, it is therefore known to provide a disposable blade made up of a combination of materials. U.S. Pat. No. 5,769,434 discloses a disposable blade of light, inexpensive material plus a contact blade of more expensive, harder material. However, the blade is relatively complex, including a stabilization rail of metal, carbon fibre surrounded by the blade, and a contact blade comprising a metal band either glued onto the bottom surface of the blade or held in place below the blade by an embedded strip of gripping ridges.
Another composite blade is disclosed in U.S. Pub. No. 2009/0206563, which describes a blade comprising a pair of metal plates separated by one or more metal webs, all partially encompassed by a rigid polymeric portion, which may be carbon fibre-reinforced epoxy. The metal plates form the edges of the contact blade, while the metal webs extend between the plates, leaving voids which are filled with plastic, though internal voids may be left empty. U.S. Pat. No. 6,761,363 shows a blade comprising a lower ice-contacting portion runner primarily made of metal, having a narrowed upper section around which a polymer is injection moulded, including spaced holes in the metal for secure bonding with the polymer. It is also known to sandwich a hard plastic or composite filler material between metal blade sides, as in Chinese Patent App. No. 101244334. In each case, the presence of metal substantially throughout the blade means that the blade is relatively heavy, compared to a blade comprising mostly a polymeric or other lighter material.
Canadian Patent No. 2786312 discloses a disposable composite blade comprising a metal ice-contacting edge bonded to metal foil, which is in turn wrapped around a plastic core. Additional layers may be added between the core and foil, or as external layers bonded to the foil, to increase the stiffness of the blade. A reinforcing mat pre-impregnated with epoxy/resin may be added as another wrapping layer to further increase the strength of the blade without adding substantial weight to the blade. However, the need for many layers of foil and a number of parts makes this blade relatively complex to manufacture, which tends to increase the cost of the finished product. The use of a single piece of plastic as the core may also limit the ability to optimize the blade properties.
U.S. Pat. No. 5,248,156 discloses a runner that takes the form of a thin flexible strip of metal to be secured directly to the blade holder of a skate, or to a blade inserted into the holder. The thinness and small size of the metal strip means that it may be easily disposed of, although the durability of same may be questionable. Further, the skate radius or other properties are not easily altered without permanently grinding the blade holder, and the connection mechanism is relatively complicated. Finally, the runner cannot be sharpened, nor is it reversible, meaning that it is necessary to carry a spare set of runner strips in case the blade is damaged unexpectedly.
It is therefore an object of the invention to provide a double-edged disposable blade for an ice skate that overcomes the foregoing deficiencies.
It is yet a further object of the invention to provide a reversible, disposable skate blade for a skate blade assembly having supports on either side of a skate blade to allow fast and secure removal and installation of the blade without having to remove the skate from the foot. These supports may be formed with the blade for simplicity of use, or may be separate pieces to allow for greater flexibility in replacing the various components of the blade assembly.
These and other objects of the invention will be appreciated by reference to the summary of the invention and to the detailed description of the preferred embodiment that follow. It will be noted that not all objects of the invention are necessarily realized in all possible embodiments of the invention as defined by each claim.